Their basement was filled with $20,000 worth of merchandise for free, and all of it is going to charity.

When I walked into the basement, I was amazed. It was filled with bags of clothes, boxes of food, and thousands of dollars worth of toiletry items. Chris Duff told me the merchandise was valued at about $20,000, and he’d gotten all of it for free.

Chris and his wife, Ashley, are extreme couponers who are using their talents to change people's lives. They keep about 10 percent of what they buy and give the rest to charity.

The Duffs spend about eight hours a week clipping coupons, going through sales fliers and then matching them up for maximum savings. They get their coupons from the Sunday inserts, but to save the way they do, they have to buy a lot of newspapers. They usually pick up 20 Sunday papers.

On TLC’s show "Extreme Couponing," the Monongahela couple bought $1,000 worth of groceries for free. Chris told me it all began when he was 7, when his single mom was trying to put food on the table for three kids.

"We had to do the food stamps. We stood in line at food banks with a box with our name on it, you know? And it's a little humiliating," said Duff.

Now he's the one donating thousands of dollars worth of food to charities in Washington County.

"I wanted to give back, because I've been there. I know what's it's like to be in need,” said Duff, who is now a ministry student.

The Duffs search the clearance racks for deals. They showed me 400 shirts, worth $8,000, that they got for free.

"It went on clearance for $5 a pop. We had a $5 coupon. It made it all free," said Duff.

Ashley was proud of the 12,000 toothbrushes they got with coupons at Rite Aid that are now bound for the Dominican Republic.

Ashley told me she wasn't always an extreme couponer. She started out just trying to save on groceries for her family.

"We tell people to buy one paper for each person in their family," said Duff.

To save the way the Duffs do, you have to learn how to combine coupons with store sales.

"I realized that getting things for free is awesome. And to share that with others is even better."

On Saturday, Oct. 22, the Duffs are teaching a free class on couponing at The Central Assembly of God Church in Houston, Pa. The session runs from 10 a.m. until noon.

The church seats 800 people. The Duffs are asking people to RSVP, so they don’t have to turn anyone away at the door. The number to call is 724-746-4900.